android exception NetworkOnMainThreadException (Already used asyncTask but still error)

Question

I am building a simple android app but I keep getting this exception NetworkOnMainThreadException. I have researched a lot about this, I understand that on android3.0(honeycomb) os and above, it is stricter, and should use asyncTask (on background thread), and I have done everything that I found, but still getting this exception, could someone guide on how to fix this ?

EditProductActivity.java :

package com.example.test;

import java.util.ArrayList;
import java.util.List;

import org.apache.http.NameValuePair;
import org.apache.http.message.BasicNameValuePair;
import org.json.JSONArray;
import org.json.JSONException;
import org.json.JSONObject;

import android.app.Activity;
import android.app.ProgressDialog;
import android.content.Intent;
import android.os.AsyncTask;
import android.os.Bundle;
import android.util.Log;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;

public class EditProductActivity extends Activity {

    EditText txtName;
    EditText txtPrice;
    EditText txtDesc;
    EditText txtCreatedAt;
    Button btnSave;
    Button btnDelete;

    String pid;

    //progress Dialog
    private ProgressDialog pDialog;

    //JSON parser class
    JSONParser jsonParser = new JSONParser();

    //single product url
    private static final String url_product_details = "http://api.kerjaapa.com/android_connect/get_product_details.php";

    //url to update product
    private static final String url_update_product = "http://api.kerjaapa.com/android_connect/update_product.php";

    //url to delete product
    private static final String url_delete_product = "http://api.kerjaapa.com/android_connect/delete_product.php";

    //JSON Node names
    private static final String TAG_SUCCESS = "success";
    private static final String TAG_PRODUCT = "product";
    private static final String TAG_PID = "pid";
    private static final String TAG_NAME = "name";
    private static final String TAG_PRICE = "price";
    private static final String TAG_DESCRIPTION = "description";

    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.edit_product);

        //save button
        btnSave = (Button) findViewById(R.id.btnSave);
        btnDelete = (Button) findViewById(R.id.btnDelete);

        //getting product details from intent
        Intent i = getIntent();

        //getting product id(pid) from intent
        pid = i.getStringExtra(TAG_PID);

        //getting complete product details in background thread
        new GetProductDetails().execute();

        //save button click event
        btnSave.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View arg0) {
                //starting background task to update product
                new SaveProductDetails().execute();
            }
        });

        //Delete button click event
        btnDelete.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View arg0) {
                //deleting product in background thread
                new DeleteProduct().execute();
            }
        });
    }

    //Background Async Task to Get Complete Product Details
    class GetProductDetails extends AsyncTask<String, String, String> {
        //Before starting background thread show progress dialog
        @Override
        protected void onPreExecute() {
            super.onPreExecute();
            pDialog = new ProgressDialog(EditProductActivity.this);
            pDialog.setMessage("Loading product details. Please wait...");
            pDialog.setIndeterminate(false);
            pDialog.setCancelable(true);
            pDialog.show();
        }

        //getting product details in background thread
        protected String doInBackground(String... params) {
            //updating UI from Background Thread
            runOnUiThread(new Runnable() {
                public void run() {
                    //Check for success tag
                    int success;
                    try {
                        //Building Parameters
                        List<NameValuePair> params = new ArrayList<NameValuePair>();
                        params.add(new BasicNameValuePair("pid", pid));

                        //getting product details by making HTTP request
                        //Note that product details url will use GET request
                        JSONObject json = jsonParser.makeHttpRequest(
                            url_product_details, "GET", params);

                        //check your log for json response
                        Log.d("Single Product Details", json.toString());

                        //json success tag
                        success = json.getInt(TAG_SUCCESS);
                        if (success == 1) {
                            //successfully received product details
                            JSONArray productObj = json
                                .getJSONArray(TAG_PRODUCT); //JSON Array

                            //get first product object from JSON Array
                            JSONObject product = productObj.getJSONObject(0);

                            //product with this pid found
                            //Edit text
                            txtName = (EditText) findViewById(R.id.inputName);
                            txtPrice = (EditText) findViewById(R.id.inputPrice);
                            txtDesc = (EditText) findViewById(R.id.inputDesc);

                            //display product data in editText
                            txtName.setText(product.getString(TAG_NAME));
                            txtPrice.setText(product.getString(TAG_PRICE));
                            txtDesc.setText(product.getString(TAG_DESCRIPTION));

                        } else {
                            //product with pid not found
                        }
                    } catch (JSONException e) {
                        e.printStackTrace();
                        }
                    }
                });

            return null;
        }

        //After completing background task dismiss the progress dialog
        protected void onPostExecute(String file_url) {
            //dismiss the dialog once got all details
            pDialog.dismiss();
        }

    }

    //Background Async Task to Save product details
    class SaveProductDetails extends AsyncTask<String, String, String> {

        //Before starting background thread, show dialog
        @Override
        protected void onPreExecute() {
            super.onPreExecute();
            pDialog = new ProgressDialog(EditProductActivity.this);
            pDialog.setMessage("Saving product ...");
            pDialog.setIndeterminate(false);
            pDialog.setCancelable(true);
            pDialog.show();
        }

        //Saving product
        protected String doInBackground(String... args) {

            //getting updated data from EditTexts
            String name = txtName.getText().toString();
            String price = txtPrice.getText().toString();
            String description = txtDesc.getText().toString();

            //Building parameters
            List<NameValuePair> params = new ArrayList<NameValuePair>();
            params.add(new BasicNameValuePair(TAG_PID, pid));
            params.add(new BasicNameValuePair(TAG_NAME, name));
            params.add(new BasicNameValuePair(TAG_PRICE, price));
            params.add(new BasicNameValuePair(TAG_DESCRIPTION, description));

            //sending modified data through http request
            //Notice that update product url accepts POST method
            JSONObject json = jsonParser.makeHttpRequest(url_update_product, 
                "POST", params);

            //check json success tag
            try {
                int success = json.getInt(TAG_SUCCESS);

                if (success == 1) {
                    //successfully updated
                    Intent i = getIntent();
                    //send result code 100 to notify about product update
                    setResult(100, i);
                    finish();
                } else {
                    //failed to update product
                }
            } catch (JSONException e) {
                e.printStackTrace();
            }

            return null;
        }

        //After completing background task, dismiss dialog
        protected void onPostExecute(String file_url) {
            //dismiss dialog
            pDialog.dismiss();
        }
    }

    //Background async task to delete product
    class DeleteProduct extends AsyncTask<String, String, String> {

        //Before starting, show progress dialog
        @Override
        protected void onPreExecute() {
            super.onPreExecute();
            pDialog = new ProgressDialog(EditProductActivity.this);
            pDialog.setMessage("Deleting Product...");
            pDialog.setIndeterminate(false);
            pDialog.setCancelable(true);
            pDialog.show();
        }

        //Deleting product
        protected String doInBackground(String... args) {


            //check for success tag
            int success;
            try {
                //Building parameters
                List<NameValuePair> params = new ArrayList<NameValuePair>();
                params.add(new BasicNameValuePair("pid", pid));

                //getting product details by making HTTP request
                JSONObject json = jsonParser.makeHttpRequest(
                    url_delete_product, "POST", params);

                //check your log for json response
                Log.d("Delete product", json.toString());

                //json success tag
                success = json.getInt(TAG_SUCCESS);
                if (success == 1) {
                    //product successfully deleted
                    //notify previous activity by sending code 100
                    Intent i = getIntent();
                    //send result code 100 to notify about product deletion
                    setResult(100, i);
                    finish();
                }
            } catch (JSONException e) {
                e.printStackTrace();
            }

            return null;
        }

        //After completing background task dismiss dialog
        protected void onPostExecute(String file_url) {
            //dismiss dialog once finish
            pDialog.dismiss();
        }
    }

}

And for the layout xml:

edit_product.xml :

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="vertical" >

    <!-- Name Label -->
    <TextView android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        android:text="Product Name"
        android:paddingLeft="10dip"
        android:paddingRight="10dip"
        android:paddingTop="10dip"
        android:textSize="17dip" />

    <!-- Input Name -->
    <EditText android:id="@+id/inputName"
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        android:layout_margin="5dip"
        android:layout_marginBottom="15dip"
        android:singleLine="true" />

    <!-- Price Label -->
    <TextView android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        android:text="Price"
        android:paddingLeft="10dip"
        android:paddingRight="10dip"
        android:paddingTop="10dip"
        android:textSize="17dip" />

    <!-- Input Price -->
    <EditText android:id="@+id/inputPrice"
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        android:layout_margin="5dip"
        android:layout_marginBottom="15dip"
        android:singleLine="true" 
        android:inputType="numberDecimal" />

    <!-- Description Label -->
    <TextView android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        android:text="Description"
        android:paddingLeft="10dip"
        android:paddingRight="10dip"
        android:paddingTop="10dip"
        android:textSize="17dip" />

    <!-- Input Description -->
    <EditText android:id="@+id/inputDesc"
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        android:layout_margin="5dip"
        android:layout_marginBottom="15dip"
        android:lines="4"
        android:gravity="top" />

    <LinearLayout android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        android:orientation="horizontal">

        <!-- Button Update Product -->
        <Button android:id="@+id/btnSave"
            android:layout_width="fill_parent"
            android:layout_height="wrap_content"
            android:text="Save Changes"
            android:layout_weight="1" />

        <!-- Button Delete Product -->
        <Button android:id="@+id/btnDelete"
            android:layout_width="fill_parent"
            android:layout_height="wrap_content"
            android:text="Delete"
            android:layout_weight="1" />

    </LinearLayout>


</LinearLayout>

Here is the debug error stack :

Thread [<1> main] (Suspended (exception NetworkOnMainThreadException))

DefaultRequestDirector.execute(HttpHost, HttpRequest, HttpContext) line: 531
DefaultHttpClient(AbstractHttpClient).execute(HttpHost, HttpRequest, HttpContext) line: 555 DefaultHttpClient(AbstractHttpClient).execute(HttpUriRequest, HttpContext) line: 487
DefaultHttpClient(AbstractHttpClient).execute(HttpUriRequest) line: 465 JSONParser.makeHttpRequest(String, String, List) line: 61
EditProductActivity$GetProductDetails$1.run() line: 120 Handler.handleCallback(Message) line: 733
Handler.dispatchMessage(Message) line: 95
Looper.loop() line: 136 ActivityThread.main(String[]) line: 5017
Method.invokeNative(Object, Object[], Class, Class[], Class, int, boolean) line: not available [native method]
Method.invoke(Object, Object...) line: 515
ZygoteInit$MethodAndArgsCaller.run() line: 779
ZygoteInit.main(String[]) line: 595 NativeStart.main(String[]) line: not available [native method]

I think I have followed the rules in using asyncTask, doing the task on the background using onPreExecute(), onPostExecute(). I'm sorry I'm a newbie, any help is greatly appreciated. Thx in advance.

Answer 1

doInBackground does not interact with the main UI thread and you have mentioned Views in the doinBackground method of AsynTask

also remove runOnUIThread from doInBackground

also put these in onPostExecute method

 //product with this pid found
//Edit text
                            txtName = (EditText) findViewById(R.id.inputName);
                            txtPrice = (EditText) findViewById(R.id.inputPrice);
                            txtDesc = (EditText) findViewById(R.id.inputDesc);

                            //display product data in editText
                            txtName.setText(product.getString(TAG_NAME));
                            txtPrice.setText(product.getString(TAG_PRICE));
                            txtDesc.setText(product.getString(TAG_DESCRIPTION));

Answer 2

your doInBackground method is calling runOnUIThread, this is nonsense.

You should do your background work on doInBackground, and then execute the UI work in the onPostExecute, for example:

package com.example.test;

import java.util.ArrayList;
import java.util.List;

import org.apache.http.NameValuePair;
import org.apache.http.message.BasicNameValuePair;
import org.json.JSONArray;
import org.json.JSONException;
import org.json.JSONObject;

import android.app.Activity;
import android.app.ProgressDialog;
import android.content.Intent;
import android.os.AsyncTask;
import android.os.Bundle;
import android.util.Log;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;

public class EditProductActivity extends Activity {

    EditText txtName;
    EditText txtPrice;
    EditText txtDesc;
    EditText txtCreatedAt;
    Button btnSave;
    Button btnDelete;

    String pid;

    //progress Dialog
    private ProgressDialog pDialog;

    //JSON parser class
    JSONParser jsonParser = new JSONParser();

    //single product url
    private static final String url_product_details = "http://api.kerjaapa.com/android_connect/get_product_details.php";

    //url to update product
    private static final String url_update_product = "http://api.kerjaapa.com/android_connect/update_product.php";

    //url to delete product
    private static final String url_delete_product = "http://api.kerjaapa.com/android_connect/delete_product.php";

    //JSON Node names
    private static final String TAG_SUCCESS = "success";
    private static final String TAG_PRODUCT = "product";
    private static final String TAG_PID = "pid";
    private static final String TAG_NAME = "name";
    private static final String TAG_PRICE = "price";
    private static final String TAG_DESCRIPTION = "description";

    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.edit_product);

        //save button
        btnSave = (Button) findViewById(R.id.btnSave);
        btnDelete = (Button) findViewById(R.id.btnDelete);

        //getting product details from intent
        Intent i = getIntent();

        //getting product id(pid) from intent
        pid = i.getStringExtra(TAG_PID);

        //getting complete product details in background thread
        new GetProductDetails().execute();

        //save button click event
        btnSave.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View arg0) {
                //starting background task to update product
                new SaveProductDetails().execute();
            }
        });

        //Delete button click event
        btnDelete.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View arg0) {
                //deleting product in background thread
                new DeleteProduct().execute();
            }
        });
    }

    //Background Async Task to Get Complete Product Details
    class GetProductDetails extends AsyncTask<String, String, Integer> {
        //Before starting background thread show progress dialog
        @Override
        protected void onPreExecute() {
            super.onPreExecute();
            pDialog = new ProgressDialog(EditProductActivity.this);
            pDialog.setMessage("Loading product details. Please wait...");
            pDialog.setIndeterminate(false);
            pDialog.setCancelable(true);
            pDialog.show();
        }

        //getting product details in background thread
        protected String doInBackground(String... params) {
                    //Check for success tag
                    int success = 0;
                    try {
                        //Building Parameters
                        List<NameValuePair> params = new ArrayList<NameValuePair>();
                        params.add(new BasicNameValuePair("pid", pid));

                        //getting product details by making HTTP request
                        //Note that product details url will use GET request
                        JSONObject json = jsonParser.makeHttpRequest(
                            url_product_details, "GET", params);

                        //check your log for json response
                        Log.d("Single Product Details", json.toString());

                        //json success tag
                        success = json.getInt(TAG_SUCCESS);

                    } catch (JSONException e) {
                        e.printStackTrace();
                        }
                    }
            return success;
        }

        //After completing background task dismiss the progress dialog
        protected void onPostExecute(Integer success) {
        if (success == 1) {
                    //successfully received product details
                    JSONArray productObj = json
                        .getJSONArray(TAG_PRODUCT); //JSON Array

                    //get first product object from JSON Array
                    JSONObject product = productObj.getJSONObject(0);

                    //product with this pid found
                    //Edit text
                    txtName = (EditText) findViewById(R.id.inputName);
                    txtPrice = (EditText) findViewById(R.id.inputPrice);
                    txtDesc = (EditText) findViewById(R.id.inputDesc);

                    //display product data in editText
                    txtName.setText(product.getString(TAG_NAME));
                    txtPrice.setText(product.getString(TAG_PRICE));
                    txtDesc.setText(product.getString(TAG_DESCRIPTION));

                } else {
                    //product with pid not found
                }
            //dismiss the dialog once got all details
            pDialog.dismiss();
        }

    }

    //Background Async Task to Save product details
    class SaveProductDetails extends AsyncTask<String, String, String> {

        //Before starting background thread, show dialog
        @Override
        protected void onPreExecute() {
            super.onPreExecute();
            pDialog = new ProgressDialog(EditProductActivity.this);
            pDialog.setMessage("Saving product ...");
            pDialog.setIndeterminate(false);
            pDialog.setCancelable(true);
            pDialog.show();
        }

        //Saving product
        protected String doInBackground(String... args) {

            //getting updated data from EditTexts
            String name = txtName.getText().toString();
            String price = txtPrice.getText().toString();
            String description = txtDesc.getText().toString();

            //Building parameters
            List<NameValuePair> params = new ArrayList<NameValuePair>();
            params.add(new BasicNameValuePair(TAG_PID, pid));
            params.add(new BasicNameValuePair(TAG_NAME, name));
            params.add(new BasicNameValuePair(TAG_PRICE, price));
            params.add(new BasicNameValuePair(TAG_DESCRIPTION, description));

            //sending modified data through http request
            //Notice that update product url accepts POST method
            JSONObject json = jsonParser.makeHttpRequest(url_update_product, 
                "POST", params);

            //check json success tag
            try {
                int success = json.getInt(TAG_SUCCESS);

                if (success == 1) {
                    //successfully updated
                    Intent i = getIntent();
                    //send result code 100 to notify about product update
                    setResult(100, i);
                    finish();
                } else {
                    //failed to update product
                }
            } catch (JSONException e) {
                e.printStackTrace();
            }

            return null;
        }

        //After completing background task, dismiss dialog
        protected void onPostExecute(String file_url) {
            //dismiss dialog
            pDialog.dismiss();
        }
    }

    //Background async task to delete product
    class DeleteProduct extends AsyncTask<String, String, String> {

        //Before starting, show progress dialog
        @Override
        protected void onPreExecute() {
            super.onPreExecute();
            pDialog = new ProgressDialog(EditProductActivity.this);
            pDialog.setMessage("Deleting Product...");
            pDialog.setIndeterminate(false);
            pDialog.setCancelable(true);
            pDialog.show();
        }

        //Deleting product
        protected String doInBackground(String... args) {


            //check for success tag
            int success;
            try {
                //Building parameters
                List<NameValuePair> params = new ArrayList<NameValuePair>();
                params.add(new BasicNameValuePair("pid", pid));

                //getting product details by making HTTP request
                JSONObject json = jsonParser.makeHttpRequest(
                    url_delete_product, "POST", params);

                //check your log for json response
                Log.d("Delete product", json.toString());

                //json success tag
                success = json.getInt(TAG_SUCCESS);
                if (success == 1) {
                    //product successfully deleted
                    //notify previous activity by sending code 100
                    Intent i = getIntent();
                    //send result code 100 to notify about product deletion
                    setResult(100, i);
                    finish();
                }
            } catch (JSONException e) {
                e.printStackTrace();
            }

            return null;
        }

        //After completing background task dismiss dialog
        protected void onPostExecute(String file_url) {
            //dismiss dialog once finish
            pDialog.dismiss();
        }
    }

}

Answer 3

Your doInBackground should run the network operation and post the result to onPostExecute, where you can update the UI.

Answer 4

I think I have followed the rules in using asyncTask, doing the task on the background using onPreExecute(), onPostExecute().

Not really because in your doInBackgroundyou perform the HTTP request on the UI thread:

runOnUiThread(new Runnable() {
                public void run() {

which completely defeats the purpose of using an async task.

So remove the runOnUiThread, do your request in the background and when the task is completed use the onPostExecute to update your fields.